Magnetic alloys with high intial permeability



Patented Apr. 12, 1938 MAGNETIC ALLOYS WITH HIGH INITIAL PEBMEABILITY Kotaro Honda and Tamotsu Nishina, Sendai, Japan No Drawing. Application June 5, 1935, Serial No. 25,155

8 Claims. (01. 75-428) addition of tin to the nickel-iron alloy or throme- This invention relates to improvements in magnetic alloys with high initial permeability and nickel-iron alloy. Though the element tin has more particularly to an alloy consisting mainly no reducing effect, yet it is found by many exof iron, nickel, tin, and chromium, and has for periments that the addition of tin increases the its object to provide a magnetic alloy which has initial permeability of the alloy considerably 5 a very high initial permeability in weak magnetic under the annealed state. The addition of titanifield with less hysteresis loss and higher specific um further improves the initial permeability of electric resistance and which is easy to manuthe alloy. facture and to be worked. As it is evident from the foregoing description 10 The inventors have succeeded in producing a the alloy oi this invention consists mainly of 10 magnetic alloy consisting of iron, nickel, chromiiron, nickel, chromium and tin as the main inum and tin at the properly selected proportions gredients with or without titanium, silicon and and the alloy of this invention possesses very high manganese as sub-ingredients and the alloy initial permeability in a weak magnetic held and shows a very high initial permeability and has a small hysteresis loss and a comparatively high no aging eilect and shows no change in the mag- 15 specific electric resistance and also has stable netic properties by temperature variation and magnetic properties for temperature variation its heat treatment is very simple since it needs and mechanical shock. no quenching and the necessary properties can be The alloy of this invention contains 10 to 60% developed by the annealing process only. Ac-

of iron, 40 to 90% of nickel, 0.1 to 5% of tin, cordingly the alloy of this invention is very well 20 less than 5% of chromium as the main ingrediadapted for magnetic materials for telephone and cuts. The alloy 01 this invention may also contelegraph purposes. tain as sub-ingredients from trace to 2% of What we claim as new and desire to secure by each of titanium and silicon, and from trace to Letters Patent of the United States, is:

1.5% of manganese. Silicon acts as a reducing 1. A magnetic alloy comprising 14.3% iron, 25 agent and manganese is eil'ective to facilitate 81.2% nickel, 0.2% tin and 3% chromium and cold working 01' the alloy. The alloy of the in addition thereto 0.8% silicon and 0.5% manpresent invention may be subjected to heat treatganese, said alloy having an initial permeability ment such as annealing which may be carried of 13,500, all proportions being approximate.

out by heating the alloy to the temperature of 2. A, magnetic alloy comprising 10.3% iron, 30

' about 1100 C. and then slowly cooling at the 83.5% nickel, 0.2% tin and 4% chromium and rate of about three degrees per minute in order in addition thereto 0.5% silicon and 0.5% manto develop the most desirable characteristics ganese; said alloy also containing as an auxiland no quenching is necessary. Heretoiore known iary element 1% titanium and having an initial magnetic materials necessitating quenching have permeability 01' 19,800, all proportions being ap- 35 usually shown considerable diflerence in the efproximate. fect of heat treatment corresponding to the pro- 3. A magnetic alloy containing iron in the portion of length and diameter of the material, order of 10.3 to 14.3%, nickel in the order of but the alloy of this invention shows almost no 83.5 to 81.2%, chromium in the order oi! 4 to 0 difference in size of material. 3%, silicon about .5 to .8%, manganese about 40 As actual examples, the alloy of this invention .5 and tin about .2%, said alloy being characcontainlng 01 iron. of nickel, 0.2% terized by an initial permeability of the order of tin and 3.0% of chromium, having in addiof 13,000 or more. tlon thereto 0.8% of silicon and 0.5% of manga- 4. A magnetic alloy characterized by the addinese shows the initial permeability of 13,500. tion of tin to improve its magnetic qualities and 45 By adding a proper amount of titanium to the consisting of 10 to 60% of iron, 90 to 40% of above mentioned elements the initial permeabilnickel, 0.1 to 5% of tin and 0 t o chromium ity can be increased further. As for example, as the main ingredients and from trace to 2% the alloy containing 10.3% of iron, 83.5% of each of titanium and silicon and from trace to nickel, 0.2% of tin, 4.0% of chromium, 0.5% 1.5% of manganese as the sub-ingredients. 50

of silicon, 0.5% oi. manganese and 1.0% of titani- 5. A magnetic alloy characterized by the addium shows the initial permeability of 19,800 which tion of tin to improve its magnetic qualities and is much higher than the first example. consisting of as essential ingredients 10 to The most important characteristics of the alloy of iron, to 40% of nickel and .1 to 5% oi tin, 55 01' this invention are mainly developed by the and less than 5% chromium, characterized by 55 high initial permeability in a weak magnetic field, and no aging eflect.

6. A magnetic alloy according to claim 5 including as another ingredient titanium to the extent ofnot over 2%.

'7: A magnetic alloy characterized by the addition of tin to improve its magnetic qualities and consisting of as essential ingredients 10 to 60% of iron, 90 to 40% of nickel, .1 to 5% of tin, from a trace to 2% of titanium and from a trace to 5% of chromium.

8. A- yl-Bfletic alloy according to claim 7 includingaiciurther ingredients from a trace to 2% of silicon as a reducing agent and from a a trace to 1.5% of manganese to facilitate cold working of the alloy.

KO'IARO HONDA. TAMOTSU NIBHINA. 

